1 /* Copyright (c) 2019-2022. The SimGrid Team. All rights reserved. */
3 /* This program is free software; you can redistribute it and/or modify it
4 * under the terms of the license (GNU LGPL) which comes with this package. */
6 #include "src/include/catch.hpp"
8 #include "xbt/random.hpp"
12 #define EpsilonApprox(a) Catch::Matchers::WithinAbs((a), 100 * std::numeric_limits<double>::epsilon())
14 TEST_CASE("xbt::random: Random Number Generation")
16 SECTION("Using XBT_RNG_xbt")
18 simgrid::xbt::random::set_implem_xbt();
19 simgrid::xbt::random::set_mersenne_seed(12345);
20 REQUIRE_THAT(simgrid::xbt::random::exponential(25), EpsilonApprox(0.00291934351538427348));
21 REQUIRE(simgrid::xbt::random::uniform_int(1, 6) == 4);
22 REQUIRE_THAT(simgrid::xbt::random::uniform_real(0, 1), EpsilonApprox(0.31637556043369124970));
23 REQUIRE_THAT(simgrid::xbt::random::normal(0, 2), EpsilonApprox(1.62746784745133976635));
25 constexpr int imin = std::numeric_limits<int>::min();
26 constexpr int imax = std::numeric_limits<int>::max();
27 REQUIRE(simgrid::xbt::random::uniform_int(0, 0) == 0);
28 REQUIRE(simgrid::xbt::random::uniform_int(imin, imin) == imin);
29 REQUIRE(simgrid::xbt::random::uniform_int(imax, imax) == imax);
31 REQUIRE(simgrid::xbt::random::uniform_int(-6, -1) == -3);
32 REQUIRE(simgrid::xbt::random::uniform_int(-10, 10) == 7);
33 REQUIRE(simgrid::xbt::random::uniform_int(imin, 2) == -163525263);
34 REQUIRE(simgrid::xbt::random::uniform_int(-2, imax) == 1605979225);
35 REQUIRE(simgrid::xbt::random::uniform_int(imin, imax) == 659577591);
38 SECTION("Using XBT_RNG_std")
43 simgrid::xbt::random::set_implem_std();
44 simgrid::xbt::random::set_mersenne_seed(12345);
46 std::exponential_distribution<> distA(25);
47 std::uniform_int_distribution<> distB(1, 6);
48 std::uniform_real_distribution<> distC(0, 1);
49 std::normal_distribution<> distD(0, 2);
51 REQUIRE_THAT(simgrid::xbt::random::exponential(25), EpsilonApprox(distA(gen)));
52 REQUIRE(simgrid::xbt::random::uniform_int(1, 6) == distB(gen));
53 REQUIRE_THAT(simgrid::xbt::random::uniform_real(0, 1), EpsilonApprox(distC(gen)));
54 REQUIRE_THAT(simgrid::xbt::random::normal(0, 2), EpsilonApprox(distD(gen)));
57 SECTION("XBT_RNG_std write to a file")
59 simgrid::xbt::random::set_implem_std();
60 simgrid::xbt::random::set_mersenne_seed(12345);
62 simgrid::xbt::random::exponential(25);
63 bool writtenA = simgrid::xbt::random::write_mersenne_state("rdm_state_tmp.txt");
64 double resB = simgrid::xbt::random::uniform_real(10, 20);
65 double resC = simgrid::xbt::random::normal(0, 2);
66 bool writtenB = simgrid::xbt::random::read_mersenne_state("rdm_state_tmp.txt");
69 REQUIRE_THAT(simgrid::xbt::random::uniform_real(10, 20), EpsilonApprox(resB));
70 REQUIRE_THAT(simgrid::xbt::random::normal(0, 2), EpsilonApprox(resC));
72 std::remove("rdm_state_tmp.txt");